Advance a little farther up the hill and take up a position behind the blue barrels and sandbags on the left side of the road.

Draw your weapon of choice and look up to the right to the rooftop just beyond where the 3 rope lines are anchored. There are 3 more Solarii up there. Try to shoot one of them while they're still on this roof. When you do, one of them will yell, "Here she comes! Get to ground level!" The others will then slide down the zip line toward you.

If you can shoot them off the rope, they'll fall and hopefully die before reaching you.

If they manage to make it around the corner a the top of the hill, take them out as they run down toward you.

You'll know you've killed them all when Lara stands up instead of crouching behind cover. Loot the bodies on this side of the fence, but don't go around the corner to the right (i.e., beyond the pink dashed line in the screenshot above), since this will trigger the appearance of more enemies.

Instead, pick up the pistol and rifle/SMG ammo sitting on the ground in front of the building at the top of the hill. (They're circled in the screenshot above.) Then climb up onto the ledge on the left side of that building and immediately take cover behind the broken wall on the right (as indicated by the arrows above).

As you climb up, the 3 men in the next building notice Lara and start yelling and shooting flaming arrows. As long as you stay close to the wall, they can't hit you. Turn around and face the ruined building where they're standing.

Target the red barrels on the middle level with your bow and fire.

The resulting explosion should take care of all of them. You'll also get a little XP bonus for your trouble.

Before dropping down from this ledge, go around to the opposite corner of the building, on this same level, to find a box containing a relic (1/2), Japanese Dog Tags, one of the Senshi Elite set. If you shot one of the soldiers on top of this building earlier, you can climb to the upper level to loot his body now.